The cultivation of agricultural crops has evolved over the years from the growing of crops on a large number of small family farms to the growing of crops on large scale farms. Irrespective of a farm's size, variations in terrain, soil conditions, and weather exposure can result in non-uniformities of field conditions during the preparation and growing of crops.
Individual farmers, who typically do not farm with irrigation equipment on their plots of land have learned to selectively fertilize and harvest each plot according to its specific needs. Pursuant to topological variations, some plots of land are exposed to more sunlight due to the presence of a hillside slope, better exposing the land to rays of light. Similarly, other plots of land can have an overall increased moisture content due to their presence in a valley where water is likely to collect when it rains. Typically, an individual farmer faced with the task of cultivating a small family farm, will consciously be aware of such variations. Hence, the farmer will make decisions to cultivate certain plots of land based upon their personal knowledge of soil conditions and crops being grown on each plot. Such a growing/cultivating strategy is realizable by a small scale farmer who does not have to cultivate a large number of plots of land.
In addition to sunlight exposure, individual farmers keep track of rainfall, humidity and temperature, as well as soil conditions and the occurrence of bug infestations. In some cases, soil is analyzed to determine nitrogen levels and various other conditions. In other cases, visual observation is made by a farmer as he walks through a field to detect the presence of bugs or other crop-damaging conditions. However, it is only feasible for a farmer who collects data in such a manner, to grossly categorize such agronomic information when attempting to tailor a farming strategy that maximizes crop yield therefrom. Hence, improvements that enable better collection and management of such information have been needed by individual farmers.
Additionally, the trend in agriculture has been an increase in the number of large scale farms that contain vast amounts of land, frequently divided into many plots of land. Many of these farms are run by corporations, or large groups of individuals. Due to the large amount of land being cultivated and the large number of individuals involved in such cultivation, the collection and tracking of detailed knowledge about soil and crop information over all regions of land being cultivated can be lost.
Additionally, some large scale farms employ sprinkler irrigation systems for applying water and chemicals to a crop being raised. One type of sprinkler system consists of a center-pivot irrigation device configured to apply water and chemicals to a circular plot of land. Such devices can also be adapted to irrigate square plots of land by providing end features for irrigating corner portions of such a plot via provision of a controllable end gun or articulating end boom contained therealong. A typical center pivot irrigation device has a fixed pivot, and a long body carried by an array of towers having support wheels. A plurality of sprinklers are fixed in spaced-apart relation along the arm, each sprinkler being activated via a solenoid valve to enable turning "on" and "off" of a sprinkler nozzle to regulate application of water and chemicals therefrom. In operation, the arm is rotated about the fixed pivot via the towers, as drive motors on each tower drive the support wheels, causing the device to rotate thereabout. Each sprinkler is activated via the solenoid valve to distribute water at a desired rate. The rate of application depends on the radial location of each particular sprinkler, so as to produce a somewhat uniform distribution of water around the field.
Recently, attempts have been made to enable a variable-rate application of water and chemicals to a field in order to deliver water and chemicals to regions of the field in differing amounts. One such effort is disclosed in U.S. Pat. No. 5,246,164 to McCann et al., entitled "Method and Apparatus for Variable Applications of Irrigation Water and Chemicals". A center pivot irrigation device has a plurality of sprinkler assemblies oriented in a fixed array. The array of sprinklers are operable to distribute an adjustable amount of water over a zone of ground as the arm is pivoted about the fixed pivot.
An additional area of development in the field of irrigation involves in-ground sprinkler systems that are used to irrigate relatively small plots of land. Typically, such systems consist of irrigation sprinklers that are buried in the landscaped ground surrounding large commercial buildings. Other applications include implementation of such systems on golf courses where maintenance of healthy ground cover is desirable. In one such system disclosed in U.S. Pat. No. 4,852,802 to Iggulden et al., entitled "Smart Irrigation Sprinklers", an irrigation sprinkler is disclosed which has a plurality of moisture sensing probes buried in the soil adjacent each sprinkler head. Each sensing probe is configured to develop an electrical signal representing the moisture content of soil surrounding the probe. Irrigation logic receives information on moisture content, and can compare such information with pre-established limits for preventing the supply of water to a sprinkler head when the ground is already sufficiently moist. However, such systems are impractical for use when farming large plots of land. In-ground systems are not suitable for applications where the ground must be turned over and tilled when preparing a field for the planting of crops. Likewise, in-ground sensors prove impractical because normal harvesting operations will damage or disrupt the placement of such devices. Furthermore, an extremely large number of sensing devices would be required in order to detect information from an entire field. Therefore, such an irrigation implementation on an agricultural field would prove extremely expensive. Furthermore, such a system would only provide a coarse distribution of information, because sensors would have to be spaced apart a rather significant distance in order to provide anything close to a cost-effective data collection implementation.
Another area of recent improvement in the field of agriculture involves the use of precision agriculture products. Such products typically utilize variable-rate application devices such as the above-mentioned pivot-end irrigation device, global positioning system (GPS) devices, and geographic information system (GIS). Satellite-based global positioning systems enable the determination of precise locations within a field of interest. Geographical information systems enable data management of detected conditions on a field of interest.
One presently available suitable differential global positioning system is manufactured by Trimble, and is sold under the product name Direct GPS for Arc View, Trimble Surveying and Mapping Division, 645 North Mary Avenue, P.O. Box 3642, Sunnyvale, Calif. 94088-3642.
One suitable geographic information system (GIS) is presently available from Environmental System Research Institute, Inc. (ESRI), 380 New York Street, Redlands, Calif. 92373-8100, under the name "ARCVIEW.RTM., for Agriculture". Such a GIS system enables the management of agricultural information by way of a graphical user interface. The GIS system consists of software loaded into memory and implemented on a computer, and forms a graphical user interface that easily enables a user to tabulate data and evaluate collected data for making decisions about a crop being cultivated.
The use of precision agriculture products has been coupled with far-distance data collection techniques for determining certain agronomic features on a field being studied. Satellite imaging techniques and aerial photography techniques have enabled the collection of large amounts of data in order to characterize agronomic information and features on large fields of interest. For example, thermal imaging cameras have been used to determine certain thermal characteristics that manifest themselves on a field being observed. However, such cameras produce a gray scale array of pixels having limited resolution, and further, only collect information periodically when weather conditions permit flight overhead. Such flight-based collection is performed a far distance above a field being monitored. In some circumstances, the presence of certain crop and soil conditions will manifest themselves in the form of a thermally detectable variation upon the land. Similar detection can be performed in the visible, infrared and ultraviolet ranges, enabling the determination of correlated features with such information.
However, the ability to collect agronomic information on a field of interest via far-distance detection techniques often-times has limited capabilities. For example, inclement weather conditions can prevent the collection of information by blocking the ability to detect agronomic features. For cases of satellites, even the presence of moderate cloud cover can disrupt detection of such information. During certain periods of a growing cycle for a crop, the detection of such information can be critical to successful harvesting, as well as to the implementation of remedial measures that must be taken in order to counteract the effects of a bug infestation or fungal attack on plants. Hence, an improved technique which enables the detection of such agronomic information during any time of day, and under any type of weather condition, is desired. Furthermore, a sensing device that enables the detection of an increased number of different agronomic features is also desired. Additionally, a detection device that does not harm crops during the detection process, yet enables the collection of agronomic information while crops are being grown, is also desirable.
Although a number of precision agriculture products have recently been made available to the farming community, little has been done to enhance the ability to collect large amounts of data in a way which does not interrupt with the preparation and growing of a crop on a field. Therefore, there is a present need to enhance the ability to detect information about soil conditions and crops, while substantially leaving the field uninterrupted during the data collection process.
Another presently unresolved problem is a general inability to monitor and evaluate the condition of crops during each growing cycle. Presently, an individual farmer has to selectively sample and/or observe crop characteristics during a growing cycle in order to make projections about yield and productivity. However, such a crop-yield productivity system is dependant heavily upon the number of sample observations made by an observer, as well as the particular location of such sample sights being selected. Therefore, there is a need to improve the monitoring and sampling of crop status and growing conditions in order to better make projections on crop-yield during a particular growing cycle. Such information would prove useful in predicting overall crop yields, as well as making decisions on whether or not a crop surplus is available for selling to particular customers and foreign governments.
Therefore, a need has arisen for a system which provides for collection of such agronomic information, and further provides for collection of such information in a format suitable for use with presently available geographic information systems (GIS) and global positioning systems (GPS). Hence, there is a need to provide input of such information to crop modeling programs, either on request, or automatically.
Yet another presently unresolved problem is a general inability to precisely apply water and/or chemicals locally to specific locations on a field and according to detected needs. More particularly, there is a need to apply water and/or chemicals locally, yet over large plots of land being cultivated, particularly in response to detected needs. Even further, there is a need to combine local detection of agrarian needs and application of water and/or chemicals to meet such needs within a single device capable of detecting needs and/or applying water/chemicals to meet such needs.